ロンボ型ファミリーの膜内プロテアゼの結晶構造
Yongcheng Wang1, Yingjiu Zhang, Ya Ha
1Department of Pharmacology, Yale School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520, USA.
Nature
|October 20, 2006
まとめ
Escherichia coli GlpGの結晶構造は,その活性部位が膜内にあることを明らかにし,膜内プロテオリシスが水害性環境で発生することを示唆しています. ゲーティングメカニズムは,酵素への基質アクセスを制御する可能性がある.
科学分野:
- バイオケミストリー バイオケミストリー
- 構造生物学 構造生物学とは
- メンブラン生物学 メンブラン生物学
背景:
- Escherichia coli GlpGは,ロンボイドプロテアースファミリーに属する統合膜タンパク質です.
- ロンボイドプロテアゼは,サイト-2プロテアゼ (S2P) とガンマセクレタゼに似た膜タンパク質のトランスメブラン領域を割る.
研究 の 目的:
- GlpGコアドメインの高解像度結晶構造を決定するために.
- GlpGによる膜内タンパク質分解の構造的基礎を解明する.
主な方法:
- X線結晶学を使用して,GlpGコアドメインの2.1A解像度の結晶構造を取得しました.
- タンパク質構造の分析により,主要な残留物,水分子,および基板へのアクセス経路が特定されました.
主要な成果:
- GlpG構造は,膜表面の下,タンパク質内部にある触媒的なSer-Hisダイアードを持つ6つのトランスメブランセグメントを明らかにします.
- V形の開口は,基板の横断アクセスを提供しますが,ループによって部分的に遮断され,ゲーティングメカニズムを示唆しています.
- 活性部位は,水害性膜二重層内に位置しており,ペプチド結合分裂がこの環境で発生することを示しています.
結論:
- GlpGによる膜内タンパク質分解は,水害性膜二重層内で発生する.
- 新しいゲーティングメカニズムは,GlpG.の活性部位への基板へのアクセスを制御する可能性がある.
- 構造的な洞察は,ロンボイドタンパク質酶の機能と膜内タンパク質分解の理解を進める.
関連する概念動画
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Overview
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01:29Insertion of Multi-pass Transmembrane Proteins in the RER
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The multipass transmembrane proteins are the type IV integral membrane proteins with multiple topogenic sequences determining their spatial arrangement in the ER membrane. Nearly all multipass proteins lack a cleavable signal sequence and use...
01:56Structural Protein Function
Structural proteins are a category of proteins responsible for functions ranging from cell shape and movement to providing support to major structures such as bones, cartilage, hair, and muscles. This group includes proteins such as collagen, actin, myosin, and keratin.
Collagen, the most abundant protein in mammals, is found throughout the body. In connective tissue, such as skin, ligaments, and tendons, it provides tensile strength and elasticity. In bones and teeth, it mineralizes to form...
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01:17The Proteasome Structure
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